FDA chief stepping down

Margaret Hamburg, the head of the Food and Drug Administration, is leaving her post next month.

In an e-mail to FDA employees, Hamburg said the agency's chief scientist -- Stephen Ostroff -- will serve as acting commissioner until President Obama can tap a replacement.

From the Associated Press:

"Hamburg has served in the post since 2009. In the email, she highlighted her work in creating a new food safety system, advancing the safety and effectiveness of medical products and putting new tobacco regulations in place."

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